1. Welcome to TalkBass 2014! If you're new here, we just went through a major site upgrade. Please post all concerns and bugs to the Forum Usage Issues forum. We will be monitoring that forum. Thank you for all of your feedback.

    The TalkBass iphone/android app is NOT WORKING currently. We're working on it. Tapatalk IS working, so if you need to use an app, use Tapatalk. Try using your browser though - TalkBass is now 100% responsive to your phone/tablet screen size ;)

    Please read the TalkBass 2014 FAQ for lots of great info on the new software.

Input jack, jacked?

Discussion in 'Pickups & Electronics [BG]' started by Downunderwonder, Jan 26, 2014.

  1. Downunderwonder

    Downunderwonder

    Joined:
    Aug 26, 2009
    Likes Received:
    1
    Active bass, cutting in and out when the lead plug gets wiggled. It's not the lead.

    I opened the control cavity and the 3 way jack seems all well connected and getting a good grip on the plug, yet the plug is easy enough to micro wriggle as most jacks do, while appearing not to lose contact. What's really happening?
  2. Crater

    Crater

    Joined:
    Oct 12, 2011
    Likes Received:
    0
    If it's a 'barrel style' output jack...

    [​IMG]

    ...then it's worn out. No way to repair it, just have it replaced.
  3. john m

    john m Supporting Member

    Joined:
    Jan 15, 2006
    Likes Received:
    0
    The 2 poles short together internally.

    Replace the jack.
  4. pfox14

    pfox14

    Joined:
    Dec 22, 2013
    Likes Received:
    0
    Have you tried different cords? Maybe it's not the jack at all.
  5. john m

    john m Supporting Member

    Joined:
    Jan 15, 2006
    Likes Received:
    0
  6. Groovin61

    Groovin61

    Joined:
    Feb 25, 2013
    Likes Received:
    0
    Just had the same exact thing happen on an active P I have from the late 80's. Couldn't figure it out. Took it to a tech who replaced the jack and all is well.
  7. nashvillebill

    nashvillebill

    Joined:
    Oct 13, 2002
    Likes Received:
    0
    F#maj7 = chord

    Wire that transmits signal = cord
  8. ahc

    ahc

    Joined:
    Jul 31, 2009
    Likes Received:
    1
    And... It's an OUTPUT jack. :bag:
  9. john m

    john m Supporting Member

    Joined:
    Jan 15, 2006
    Likes Received:
    0
    Spellin was my worstest subject in skool.

    I'm much better at cypherin-- be-in an injuneer.
  10. Downunderwonder

    Downunderwonder

    Joined:
    Aug 26, 2009
    Likes Received:
    1
    It's TRS, for activating the power on the electronics. Can you expand on how it can short?

    Come to think of it, the cutting out is sometimes accompanied by gank noise like a short, but then it's silent, would it not hum if it was shorted?
  11. Downunderwonder

    Downunderwonder

    Joined:
    Aug 26, 2009
    Likes Received:
    1
    Thanks for other replies, well, some of them.

    Yes, I swapped leads first.
  12. Downunderwonder

    Downunderwonder

    Joined:
    Aug 26, 2009
    Likes Received:
    1
    Not that kind, it's just a simple faceplate mounting one.
  13. pfox14

    pfox14

    Joined:
    Dec 22, 2013
    Likes Received:
    0
    LMAO - good way to start a day
  14. Crater

    Crater

    Joined:
    Oct 12, 2011
    Likes Received:
    0
    In that case, you might be able to clean it. You can use some fine grit sandpaper or even a pencil eraser. Gently clean the jack's contacts where they contact the plug. Roll the sandpaper into a small cylinder to clean the inside (ground/earth) portion of jack. Also check that the tip contact is making firm contact with the plug; if it isn't, you can try bending the contact in a bit to increase the pressure.

    If all that fails, it's a straightforward job to replace the jack.
  15. Downunderwonder

    Downunderwonder

    Joined:
    Aug 26, 2009
    Likes Received:
    1
    So, opposite of shorting? I'm still struggling with identifying the mode of failure.

    The way it's dead silent after it goes out is a bit spooky. I originally thought it was a dead battery.
  16. JTE

    JTE Supporting Member

    Joined:
    Mar 12, 2008
    Likes Received:
    1
    The T/R/S jack for active electronics works as a switch when you plug in a standard mono (T/S) plug. The tip of the plug connects to the tip connector of the jack, sending the signal to the amp. The barrel of the plug shorts the ring connector of the jack to the sleeve connector, which is ground. That's the switch that turns the battery on and off.

    So, if the jack ins't making good electrical connections at either the tip or the ring, it's either not going to send signal to the amp, or it will shut off the battery. Either way, you're likely to get no signal.

    BTW, the difference between calling the jack on your bass an "input" or and "output" is important for more than simply semantics. Understanding signal flow is critical to troubleshooting. So, knowing that the signal comes OUT of the bass and goes to the input helps you figure out what could be going wrong. Connections always need to be from an output to an input.

    John
  17. john m

    john m Supporting Member

    Joined:
    Jan 15, 2006
    Likes Received:
    0
    Internal failure could yield a short-- tip to ground.
    The input to the amp would then be shorted---
    that's how one of my old cords worked. You could unplug it from your instrument to switch axes without turning down you amplifier. A little button popped out when unplugged.
    Try it--- plug in your lead to the amp and short the tip to the sleeve--- you should get silence.
  18. PilbaraBass

    PilbaraBass

    Joined:
    Jul 19, 2004
    Likes Received:
    0
    if it's a simple faceplate mounted one, then you can access the contact pads and push them towards the centerline a bit... that will ensure better contact...

    barring that, replace the jack
  19. halfjackson

    halfjackson Supporting Member

    Joined:
    Feb 19, 2010
    Likes Received:
    0
    +1

    I just replaced a 20 year old barrel jack last week. It cost about $10, and was very easy to replace.
  20. Downunderwonder

    Downunderwonder

    Joined:
    Aug 26, 2009
    Likes Received:
    1
    It looks like all the contacts are well made. The prongs both get a significant stretch out when the plug goes in. I'll give them a little rough up and push them in some more to eliminate bad contact.

    Shorting tip to barrel on a guitar lead generally is to be avoided like the plague. That's the godawful pop you get pulling a lead out of an active channel, no way I'm doing that deliberately.

    The sound is either silent or a minor glitch when it goes out.

    Is it possible for the barrel to lose contact without corrosion? I haven't considered that at all.

Share This Page